nordmann



(No Model.) 2 SheetsSheet l. P. NORDMANN. SAFETY GUT-OUT APPARATUS FORNETWORKS OP MULTIPLE ELECTRICAL GONDUGTORS.

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WITNESSES: INVENTOH (No Model.) 2 Sheets-Sheet 2. P. NORDMANN. SAFETYOUT-OUT APPARATUS FOR NETWORKS 0F MULTIPLE ELECTRICAL OONDUGTORS.

No. 491680 9 :14. Patenteq May 16, 1893.

INVENTOR A T TORNE Y "UNITED STATES PATENT Clarice.

PAUL NORDMANN, OF BERLIN, GERMANY, ASSIGNOR 'lO SIEMENS dz HALSKE, OFSAME PLACE.

SAFETY CUT-OUT APPARATUS FOR NETWORKS OF MULTIPLE ELECTRICAL CONDUCTORS.

SPECIFICATION forming part of Letters Patent No. 497,680, dated May 16,1893.

Application filed November 25, 1892. Serial No. 453,015. (No model.)Patented in Germany September 7, 1889, No. 53,534: in France December28, 1889, No. 195,045; in Austria-Hungary April 18, 1890,110. 17,798 andNo. 41,3 16; in Italy April 22, 1390, No. 27,351; in Belgium April 26,1890, No. 90,329; in England November 16, 1890, No. 18,343, and inSwitzerland December 19,1890.N0.528/'73.

To all whom it may concern:

Be it known that I, PAUL NORDMANN, a subject of the King of Prussia,German Emperor, residing at the city of Berlin, in the German Empire,have invented new and useful Improvements in a Safety Gut-Out Apparatusfor a Network of Multiple Electrical Conductors, (for which I haveobtained Letters Patent as follows: in Germany, No, 53,53at, datedSeptember 7, 1.889; in France, No. 195,045, dated December 28,1889; inBelgium, No. 90,329, dated April 26, 1890; in Italy, No. 27,351, datedApril 22, 1890; in Switzerland, No. 528/73, dated December 19, 1890; inEngland, No. 18,343, dated Novemberltl, 1890; in Austria, No. 17,798,dated April 18, 1890, and in Hungary, No. 41,346, dated April 18,1890,)of which the following is a specification.

My invention relates to means for automatically breaking the circuits ofall of the conductors of a multiple conductor system, when the currentin any one conductor exceeds a predetermined amount. When two electricalconductors between which a dynamo-electric machine is inserted come incontact, thereby establishing a short circuit, the current produced bymeans of the machine becomes of undue strength, and may producecombustion of surrounding objects through the overheating of theconductors. In order to prevent this, fusible safety strips have beenintroduced in the circuit of the individual conductors, which melt orburn as soon as the current transmitted by the conductor exceeds acertainstrength, and thus interrupt the circuit before overheating hastaken place. This arrangement, however, does not hold good in a systemof distribution with multiple conductors wherein the lamps or othertranslating devices are in parallel between pairs of the conductors, andin parallel series between the two outermost conductors. If,

Or, in other words,

the whole resistance interposed between the external conductorsconnected to the dynamo machine will be reduced by the amount of theresistance of the lamps or translating devices in circuit between thetwo conductors in contact. In such a case, the strength of the currenttransmitted to the remaining group of lamps or other translating devices(three-wire system), or groups of lamps or other translating devicesinseries (four or five wire system) will be increased: but such increasewill not be sufficient to be dangerous, so far as regards setting fireto surrounding objects, but will act destructively upon the lamps ortranslating devices through which it is transmitted.

To obviate the objections, as stated, 1 provide means whereby when thecurrent transmitted through any one of the conductors of the systemexceeds the normal amount, the circuit of all the conductors of thesystem will be automatically broken.

In the accompanying drawings which illustrate my invention, I have shownthree different ways of automatically breaking the circuit of all theconductors of the system.

In the drawings, Figures 1 and 1 show in longitudinal section and planthe arrangement employed for rupturing the circuit by means of fusiblestrips. Fig.2 is an elevation of an arrangement wherein magnets areincluded in the separate circuits, and which serve, when any one of themis actuated, to break the circuits of all the conductors. Figs. 3 and 3show in elevation and plan, an arrangement of a mechanical device,fusible strips, and mercury cups for accomplishing the desired result.Figs. 4 and 5 diagrammatically represent two forms of devices forautomatically breaking the circuit of all of the conductors, when thecurrent in any one of the conductors exceeds a predetermined amount,applied to a three-wire system.

Referring first to Figs. 1 and 1: A indicates a conductor between theends of which is included a strip of fusible metal B, embedded in a bodyof non-conducting combustible material C, such for instance, as powderedcork and linseed oil dried, or a material otherwise known as linoleum.Any suitable non-conducting combustible material may be employed.

In Fig. 1, the strips of a five-wire system are shown embedded in asimilar bod y of nonconducting combustible material.

The operation of my invention is as follows: If a fusible strip B in anyone of the conductors A is heated by the transmission'of an excessivecurrent, it will cause the ignition of the combustible body C. This, inburning, will melt all of the strips B of the five conductors, therebyrupturing the circuit of all of these conductors.

In Fig. 2, a b c d 6 represent the main conductors of a five-Wiresystem. In each of these conductors is included an electro-magnet a l) cd c. D represents an armature pivoted at E, and normally held in theposition shown by means of a spring F, and provided at one end with ahook G, which takes under a recess H, in a plate of insulating materialI, on which are contact plates J which, when the plate I is in theposition shown, complete the circuits between the divided ends of theconductors a b 0 cl (2. K is a coiled spring connected to the end of theplate I. The operation of the device is simple. Any increase of currentin any one of the conductors CL 1) 0 (Z 6 will cause theelectro-magnetincluded in the circuit to attract the armature D, torelease the plate I, which is retracted by the spring K, and thereforebreak the circuit through all of the conductors a b 0 cl e.

Another arrangement is shown in Fig. 3. One end of each conductorct b cd e dips into a mercury cup at b c d or 6 The opposite end of each ofthe conductors is connected through fusible strips B with the rods L,pivoted at M and dipping into a mercury cup 0. Z1 0 d or 6 These pivotedportions are connected to coiled springs N. Laying over the rods L isanother series of rods 0, which carry on their ends the dependentportions 0' O which dip into the respective mercury cups a a Theoperation of this device is as follows: If an excessive current is sentthrough any one of the conductors a Z) c d e, the fusible strip Btherein will melt, in which case the rods L are drawn upward by thespring N, and acting on the rod 0, break the circuits of all theconductors by lifting the dependent portions 0' 0 out of the mercurycups a (F.

In Figs. 4 and 5, S indicates a dynamoelectric machine, and s, lampsconnected in parallel of the conductors and in parallel series with eachother.

I wish it understood that I do not limit myself in any wise to thevarious means shown and described for rupturing the circuit of all ofthe conductors of a multiple system, when" the current in any one of theconductors exceeds a predetermined amount, as very many devices can bemade for the purpose which will embody the intent of my invention.

Having thus described my invention, I claim- 1. The combination of theconductors of a multiple conductor system, and means normally inactive,but energized when the current in any one of said conductors exceeds apredetermined amount, to rupture the circuit of all of said conductors.

2. A system of electrical distribution, comprising three or moreconductors, lamps or other translating devices in parallel of two ofsaid conductors and in parallel series with each other, and meansnormally inactive, but energized when the current in any one of saidconductors exceeds a predetermined amount, to rupture the circuit of allof said conductors.

3. A system of electrical distribution, coniprising a source of electricenergy, three or more conductors, two of which are connected to theterminals of said source of electricity, lamps or other translatingdevices in parallel of two of said conductors and in parallel. serieswith each other and the conductors connected with the source of energy,and means normally inactive, but energized when the current in any oneof said conductors exceeds a predetermined amount, to rupture thecircuit of all of said conductors.

4:. In combination with a dynamo-electric machine and with theconductors of a multiple conductor system, of fusible safety strips incircuit with each of said conductors, and a body of non-conductingcombustible material enveloping said safety strips.

5. The combination with two or more conductors, of fusible safetystripsin circuit with each of said conductors, and a body of nonconductingcombustible material enveloping said safety strips.

In testimony whereof I have affixed my nature in the presence of twowitnesses.

PAUL NORDMLANN.

Witnesses:

MAX WAGNER, GEO. II. BENJAMIN.

